Approval and Promulgation of Air Quality Implementation Plans; State of Colorado; Denver PM10

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Final rule.

SUMMARY:

On July 30, 2001, the Governor of the State of Colorado submitted a State Implementation Plan (SIP) revision for the purpose of establishing a redesignation for the Denver, Colorado area from nonattainment to attainment for particulate matter with an aerodynamic diameter less than or equal to a nominal 10 microns (PM₁₀) under the 1987 standards. The Colorado Air Pollution Control Division's submittal, among other things, documents that the Denver area has attained the PM₁₀ national ambient air quality standards (NAAQS), requests redesignation to attainment and includes a maintenance plan for the area demonstrating maintenance of the PM₁₀ NAAQS for thirteen years. EPA is approving the redesignation request, maintenance plan, revisions to Colorado's Regulations No. 1 and 16, the request for the removal of Regulation No. 12 (“Diesel Inspection/Maintenance Program”) and the removal of the stationary source construction permits for six sources from the SIP because the State has met the applicable requirements of the Clean Air Act, as amended. This action is being taken under sections 107, 110, and 175A of the Clean Air Act (Act).

DATES:

This final rule is effective October 16, 2002.

ADDRESSES:

Copies of the documents relevant to this action are available for public inspection during normal business hours at the Air and Radiation Program, Environmental Protection Agency, Region VIII, 999 18th Street, Suite 300, Denver, Colorado, 80202-2466 and copies of the Incorporation by Reference material are available at the Air and Radiation Docket and Information Center, Environmental Protection Agency, 1301 Constitution Avenue, NW., Room B108, Mail Code 6102T Washington DC 20460. Copies of the State documents relevant to this action are available for public inspection at the Colorado Department of Public Health and Environment, Air Pollution Control Division, 4300 Cherry Creek Drive South, Denver, Colorado 80246-1530.

FOR FURTHER INFORMATION CONTACT:

Libby Faulk, EPA, Region VIII, (303) 312-6083.

SUPPLEMENTARY INFORMATION:

On May 23, 2002, EPA published a notice of proposed rulemaking (NPR) for approval of the redesignation of the Denver PM₁₀ nonattainment area to attainment (67 FR 36124). Throughout this document, wherever “we,” “us,” or “our” are used, we mean the Environmental Protection Agency (EPA).

Table of Contents

I. EPA's Final Action

A. What Action Is EPA Finalizing?

B. Updates to EPA's Proposed Approval

II. Response to Comments

III. Administrative Requirements

I. EPA's Final Action

A. What Action Is EPA Finalizing?

We are approving the Governor of Colorado's submittal of July 30, 2001, that requests a redesignation for the Denver nonattainment area to attainment for the 1987 PM₁₀ standards. We are using 1999-2001 ambient air quality data from the Denver PM₁₀ nonattainment area as the basis for our decision. We are also approving the maintenance plan for the Denver PM₁₀ nonattainment area, which was submitted with Colorado's July 30, 2001 redesignation request. In conjunction with the maintenance plan, the Governor also submitted revisions to Colorado's Regulation No. 1, “Emission Control For Particulates, Smokes, Carbon Monoxide, & Sulfur Oxides,” and Colorado's Regulation No. 16, “Street Sanding Emissions.” With their submittal, Colorado also requested that we remove Regulation No. 12, the “Diesel Inspection/Maintenance Program” and the stationary source construction permits that we had incorporated by reference into our April 17, 1997 approval of the PM₁₀ SIP (62 FR 18716). Thus, Regulation No. 12 and the permits for Public Service Company of Colorado's Cherokee Electric Generating Station, Purina Mills, Electron Corporation, Trigen-Colorado Energy Corporation, Rocky Mountain Bottle Company (which includes earlier permits that were issued in 1993 under the former name of Coors Brewing Company), and Conoco Refinery are being removed from the SIP with this action. We are approving this request, the maintenance plan and its accompanying regulation revisions because the Colorado Air Pollution Control Division (Colorado) has adequately addressed all of the requirements of the Act for redesignation to attainment applicable to the Denver PM₁₀ nonattainment area. Upon the effective date of this final action, the Denver area's designation status under 40 CFR part 81 will be revised to attainment. By using “Denver” or the “Denver area,” we mean Denver, Jefferson, and Douglas Counties, as well as part of Boulder, Adams and Arapahoe Counties. Please refer to our proposed action published on May 23, 2002 at 67 FR 36124 for a more detailed explanation of the redesignation requirements and analysis of how the Denver area has met those requirements.

B. Updates to EPA's Proposed Approval

i. Attainment of the PM₁₀ NAAQS

Whether an area has attained the PM₁₀ NAAQS is based exclusively upon measured air quality levels over the most recent and complete three calendar year period. See 40 CFR part 50 and 40 CFR part 50, appendix K. A State must demonstrate that an area has attained the PM₁₀ NAAQS through submittal of ambient air quality data from an ambient air monitoring network representing maximum PM₁₀ concentrations. The data, which must be quality assured and recorded in the Aerometric Information Retrieval System (AIRS), must show that the average annual number of expected exceedances for the area is less than or equal to 1.0, pursuant to 40 CFR 50.6. In making this showing, three consecutive years of complete air quality data must be used.

Our proposed approval of the Denver redesignation to attainment was based on 1998 through 2000 air quality monitoring data, however, we now have a more recent year of data available to use for the final redesignation. Thus, we are using 1999 through 2001 data for the basis of this final rulemaking. Between 1999 and 2001, Colorado operated thirteen PM₁₀ monitors, which were either State and Local Air Monitoring Stations (SLAMS) or National Air Monitoring Sites (NAMS), in the Denver PM₁₀ nonattainment area. Data from these monitors have been quality-assured and placed in AIRS on a quarterly basis. Only one exceedance of the 24-hour PM₁₀ NAAQS was measured between 1999 and 2001. In 1999, the Adams City monitor recorded a 24-hour value of 160 μg/m³ (the 24-hour PM₁₀ NAAQS is 150 μg/m³). Because data collection was less than 100% at this monitoring site, the expected exceedance rate for 1999 at this site was 1.16, (as calculated according to 40 CFR part 50, appendix K). For 2000 and 2001, the expected exceedance rate was 0.0. Thus, the three-year average was less than 1.0, which indicates the Denver area attained the 24-hour PM₁₀ NAAQS. All other sites had expected exceedance rates of 0.0 for this three-year period. Review of the annual standard for calendar years 1999, 2000 and 2001 reveals that the Denver area has also attained the annual PM₁₀ NAAQS. There was no violation of the annual standard for the three year period from 1999 through 2001. Further information on PM₁₀ monitoring is presented in Chapter 3, section B of the redesignation request and maintenance plan. We have evaluated the ambient air quality data and believe that Colorado has adequately demonstrated that the PM₁₀ NAAQS have been attained in the Denver area.

ii. Conoco Consent Decree

In the proposed approval of the redesignation request and maintenance plan, we explained that we were relying on a proposed federal consent decree that would require significant emission reductions at the Conoco facility before 2015. On December 20, 2001, a proposed Complaint and Consent Decree in United States v. Conoco Inc. was lodged with the United States District Court for the Southern District of Texas. (See 67 FR 107 for the notice of lodged consent decree.) That consent decree was entered by the Court on April 29, 2002. Under the consent decree, Conoco Denver Refinery's fluid catalytic cracking unit (FCCU) is required to comply with a New Source Performance Standard (NSPS), subpart J, emissions limit for PM of 1 pound per 1000 pounds of coke burned by no later than June 30, 2006. This restriction will limit Conoco to approximately 67 tons per year of primary PM₁₀, which is far less than the 1233 tons per year which Colorado used to re-model Conoco's emissions and less than the 185 tons per year Colorado used in the maintenance plan; this new limit will more than offset the 0.3 μg/m³ increase that Colorado projected based on the 1233 tons per year value and that would have affected the year 2015 “safety margin” allocation for mobile sources. Because it is based on an NSPS requirement, this new PM limit at Conoco will be permanent.

II. Summary of Public Comments and EPA's Responses

(1) Comment: One commentor expressed concern that it was unclear whether the commitment that Colorado has made in the PM₁₀ maintenance plan to revise the maintenance demonstration using the new mobile source emissions model (MOBILE6) is enforceable. The commentor believes that it is important that mobile source modeling uses MOBILE6 when emission reduction credits are taken for the federal Tier II emission standards and pointed out that EPA has acknowledged that Tier II assumptions may not be as accurate when MOBILE5 is used instead of MOBILE6.

Response: Colorado's commitment was adopted through Colorado's SIP process and is part of the maintenance plan. With the effective date of this final action, this commitment will be an enforceable part of Colorado's SIP. In addition, the SIP doesn't take credit for the Tier II program until 2004, and we expect Colorado to have fulfilled their commitment to revise the maintenance plan using MOBILE6 by that time.

(2) Comment: One commentor expressed concern that the recent EPA announcement of future revisions to the new source review (NSR) program may have implications for this redesignation and maintenance plan. The commentor also stated that in taking final action on the Denver PM₁₀ redesignation and maintenance plan, we should clarify that any SIP revision implementing the federal NSR changes must analyze the suite of air quality implications associated with such changes.

Response: To the extent these comments on the possible NSR program revisions pertain to NSR under Part D of the CAA, they are irrelevant to the Denver PM₁₀ redesignation because the area will be subject to the prevention of significant deterioration requirements (PSD) under Part C of the Clean Air Act upon redesignation to attainment. The Denver PM₁₀ maintenance plan is premised upon PSD applying to the area rather than the NSR requirements under Part D of the Act. To the extent the comments pertain to PSD, EPA has not yet taken final action regarding the changes to the NSR program; thus, the effect of any possible changes to the PSD program is speculative. Furthermore, Colorado's existing PSD regulations will remain part of the SIP until EPA approves a change to those regulations following notice and comment rulemaking. Thus, if EPA were to take final action on changes to the PSD program, Colorado would then have to revise their State PSD regulations and submit those revisions to us for approval. Any PSD program change that would affect Denver's continued maintenance of the PM₁₀ standard, or any other NAAQS, would be evaluated at that time.

(3) Comment: One commentor asked why there were significant and inexplicable differences between the onroad NO_X mobile source emissions budgets in the ozone maintenance plan and the PM₁₀ maintenance plan. The commentor noted that the differences between the NO_X budgets in the ozone maintenance plan and the NO_X budgets in the PM₁₀ maintenance plan may be based on seasonality.

Response: The commentor is correct in pointing out that one reason for the difference between the NO_X emission inventories in the PM₁₀ maintenance plan and the ozone maintenance plan is that the ozone plan uses a summertime inventory, whereas the PM₁₀ maintenance plan uses a wintertime inventory. Aside from this seasonal variation, we believe that the differences between the NO_X emissions in the two maintenance plans result from the following: (1) While the nonattainment areas for both pollutants were the same, the emissions inventory domains differ. The ozone emissions inventory includes the entire nonattainment area while the PM₁₀ maintenance plan covers a smaller area than the actual nonattainment area, although all areas with the expected maximum PM₁₀ concentrations are included in the domain; (2) The PM₁₀ maintenance plan takes emission reduction credit from EPA's Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control Requirements, which take effect in 2004, and EPA's Heavy Duty Engines and Vehicle Standards and Highway Diesel Sulfur Control Requirements, which take effect in 2007. The ozone maintenance plan does not take emission reduction credit from these control programs; (3) The vehicle miles traveled (VMT) is higher in the summertime versus the wintertime; and (4) The mobile source emission modeling inputs for the ozone plan came from the Denver Regional Council of Government's (DRCOG) 1999 through 2004 Transportation Improvement Program (TIP) while the modeling inputs for the PM₁₀ maintenance plan are based on DRCOG's more recent 2001 through 2006 TIP. We believe that the difference in the NO_X inventories between the ozone and PM₁₀ maintenance plans is reasonable and that these numbers are accurate.

III. Administrative Requirements

Under Executive Order 12866 (58 FR 51735, October 4, 1993), this action is not a “significant regulatory action” and therefore is not subject to review by the Office of Management and Budget. For this reason, this action is also not subject to Executive Order 13211, “Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use” (66 FR 28355, May 22, 2001). This action merely approves state law as meeting Federal requirements and imposes no additional requirements beyond those imposed by state law. Accordingly, the Administrator certifies that this rule will not have a significant economic impact on a substantial number of small entities under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.). Because this rule approves pre-existing requirements under state law and does not impose any additional enforceable duty beyond that required by state law, it does not contain any unfunded mandate or significantly or uniquely affect small governments, as described in the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4).

This rule also does not have tribal implications because it will not have a substantial direct effect on one or more Indian tribes, on the relationship between the Federal Government and Indian tribes, or on the distribution of power and responsibilities between the Federal Government and Indian tribes, as specified by Executive Order 13175 (65 FR 67249, November 9, 2000). This action also does not have Federalism implications because it does not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government, as specified in Executive Order 13132 (64 FR 43255, August 10, 1999). This action merely approves a state rule implementing a Federal standard, and does not alter the relationship or the distribution of power and responsibilities established in the Clean Air Act. This rule also is not subject to Executive Order 13045 “Protection of Children from Environmental Health Risks and Safety Risks” (62 FR 19885, April 23, 1997), because it is not economically significant.

In reviewing SIP submissions, EPA's role is to approve state choices, provided that they meet the criteria of the Clean Air Act. In this context, in the absence of a prior existing requirement for the State to use voluntary consensus standards (VCS), EPA has no authority to disapprove a SIP submission for failure to use VCS. It would thus be inconsistent with applicable law for EPA, when it reviews a SIP submission, to use VCS in place of a SIP submission that otherwise satisfies the provisions of the Clean Air Act. Thus, the requirements of section 12(d) of the National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) do not apply. This rule does not impose an information collection burden under the provisions of the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.).

The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the Small Business Regulatory Enforcement Fairness Act of 1996, generally provides that before a rule may take effect, the agency promulgating the rule must submit a rule report, which includes a copy of the rule, to each House of the Congress and to the Comptroller General of the United States. EPA will submit a report containing this rule and other required information to the U.S. Senate, the U.S. House of Representatives, and the Comptroller General of the United States prior to publication of the rule in the Federal Register. A major rule cannot take effect until 60 days after it is published in the Federal Register. This action is not a “major rule” as defined by 5 U.S.C. 804(2).

Under section 307(b)(1) of the Clean Air Act, petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by November 15, 2002. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of this rule for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such rule or action. This action may not be challenged later in proceedings to enforce its requirements. (See section 307(b)(2).)

List of Subjects

40 CFR Part 52

• Environmental protection
• Air pollution control
• Incorporation by reference
• Intergovernmental relations
• Particulate matter
• Reporting and recordkeeping requirements

40 CFR Part 81

• Environmental protection
• Air pollution control

Chapter I, title 40, parts 52 and 81 of the Code of Federal Regulations is amended as follows:

PART 52—[AMENDED]

1. The authority citation for Part 52 continues to read as follows:

Authority:42 U.S.C. 7401 et seq.

Subpart G—Colorado

2. Section 52.320 is amended by adding paragraph (c)(95) to read as follows:

3. Section 52.332 is amended by adding paragraph (1) to read as follows:

PART 81—[AMENDED]

1. The authority citation for part 81 continues to read as follows:

Authority:42 U.S.C. 7401 et seq.

2. In § 81.306, the table entitled “Colorado—PM-10” is amended by revising the entry under Adams, Denver, and Boulder Counties for the “Denver Metropolitan area” to read as follows: